title: [Microbubbles enhanced HIFU ablation on rabbit hepatic VX2 tumors: detecting residual tumor with contrast-enhanced ultrasound and spiral CT].
abstract: OBJECTIVE
  To assess the application of gray-scale contrast-enhanced ultrasound (CEUS) and contrast-enhanced spiral computed tomography (CECT) in detection of residual tumor after high intensity focused ultrasound (HIFU) ablation with microbubbles on rabbit hepatic VX2 tumors.
  
  
  METHODS
  Forty rabbits with hepatic VX2 tumors were randomly divided into three groups before ablation. Group I (n=10) served as sham ablation controls, rabbits in group II (n=15) and group III (n=15) were ablated using HIFU under the manipulation of computer. A bolus of 0.2 ml SonoVue solution was injected via ear marginal vein of rabbits in group III before ablation. Tumors were examined with CEUS and CECT before and within 3h after HIFU ablation. Necropsy and histopathological assessment were performed immediately after the completion of images evaluation.
  
  
  RESULTS
  Before ablation, intense arterial feeding vessels was detected in the tumors (77.5%,31/40 Compared with 52.5%,21/40) or the periphery of the tumors (22.5%,9/40 Compared with 47.5%,19/40) by CEUS and CECT, respectively. The tumors were characterized by quick wash-in and wash-out (high and rapid peak of enhancement in the arterial phase,followed by a fast decrease in enhancement level). The dose parameters used to achieve therapeutic effect in group III were significantly lower than those in group II(P<0.01). There were local residual viable tumor tissues due to incomplete ablation in 60.0% (9/15) of group II and 13.3% (2/15) of group III revealed by histopathology(P<0.05). The concordance rate of CECT and CEUS with histopathology on residual tumor detection was 27.3% and 81.8% (P<0.05), respectively.
  
  
  CONCLUSIONS
  The administration of microbubble agent enhances the efficacy of HIFU on rabbit hepatic VX2 tumors. CEUS is more sensitive than CECT in detection of residual viable rabbit VX2 tumor after HIFU.
authors.affiliation: Department of Ultrasound,Third Xiangya Hospital of Central South University,Changsha 410013, China.
authors.forename: Wei
authors.initials: W
authors.lastname: He
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Song
authors.initials: S
authors.lastname: Peng
mesh_terms: D000818:Animals; D005260:Female; D057086:High-Intensity Focused Ultrasound Ablation; D008114:Liver Neoplasms, Experimental / Q000628:therapy*; D008297:Male; D045423:Microbubbles; D018365:Neoplasm, Residual / Q000000981:diagnostic imaging / Q000473:pathology; D010743:Phospholipids; D011817:Rabbits; D013459:Sulfur Hexafluoride; D036542:Tomography, Spiral Computed; D014463:Ultrasonography
chemical_list: D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride